山区农业气候资源空间分布的推算方法及小地形的气候效应

THE METHODS CALCULATING THE SPATIAL DISTRIBUTION OF AGROCLIMATIC RESOURCES IN MOUNTAINOUS AREAS AND THE CLIMATIC EFFECTS OF MICROTOPOGRAPHY

本文提出了山区农业气候资源(温度、湿度、降水、风速等)空间分布的推算方法。为适应计算机技术在山地气候研究中的开发应用,作者使推算模式函数化,便于用计算机绘制山区小网格农业气候资源空间分布图。文中也提供了上述多项农业气候资源的小地形效应值。本文提出的推算方法在福建省沙溪流域实际应用的结果表明,能有效地揭示山区农业气候资源空间分布的宏观与微观变化,效果是令人满意的,精度也是高的。

In this paper, the methods calculating the spatial distribution of agroclimatic resources (temperature, humidity, precipitation, wind speed, etc.) in mountainous areas are presented. For suiting to the application of computer in the research of mountain climate, the calculating models are represented by functional relations and the spatial distribution maps of agro-climatic resources on fine mesh are drawed up by computer. The climatic effects of topography obtained from the application of these methods in the Shaxi River basin, in the midwest of Fujian Province, are also introduced. The effects of microtopography on thermal resources can be divided into four types: the temperature-increasing, -decreasing, -variable and -invariable, in which the greatest increasing and decreasing effects correspond to the effects of decrease and increase by 100-250 m in elevation respectively. The effect of meso- and microtopography on precipitation is affected by the topography and the prevailing wind direction with precipitation. And the effect of microtopography on wind speed is related to the topography and the angle between the wind direction and the topography. The spatial distribution maps of accumulated temperature above 10℃ (∑t10) and annual precipitation (P) in the Shaxi River basin show that the methods of calculation proposed in this paper may effectively disclose the macro and micro variations of spatial distribution of agroclimatic resources in mountainous areas, and their effects are very satisfactory.